Malicious PDF — malware analysis report

Static analysis result for SHA-256 d88a1e91d7ec1a1f…

MALICIOUS

PDF

92.6 KB Created: 2021-07-13 19:47:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cbb0643af7153ccc2747389aaa1cd74b SHA-1: 8bacd8dbbdc3fc442bf55c0e0656a46fc96fe3e1 SHA-256: d88a1e91d7ec1a1f625068de3e7529dffce30fc44c2eb3079ebf3c00533e2137
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF contains a large number of links, many pointing to compromised CMS uploads and disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were directly extracted, the nature of the links and the PDF structure are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://rts-wm.com/ckfinder/userfiles/files/xatulufikaselufezuwagobun.pdf
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acc0bac047d---fovax.pdf
    • https://ajwatravel.com/wheelmarine/userfiles/file/jibibuvojesulibipexep.pdf
    • http://talleresjpg.es/img/file/zepunakul.pdf
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfda6a68c90---21546738679.pdf
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/09b2504fd9cc59e311ab71618fbc6b2c/2883528948.pdf
    • https://kipass.fr/userfiles/file/11917519235.pdf
    • https://sellerflows.com/wp-content/plugins/super-forms/uploads/php/files/26d2c413ff04c428e5d5c47c919b23e2/34655918542.pdf
    • http://wittlich-luexem.de/userfiles/file/6201336276.pdf
    • https://ceccarbotosani.ro/userfiles/file/tupijixava.pdf
    • https://armagedonspedycja.pl/files/file/lenejetutetobaloxob.pdf
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/9bd6d763ff54f967d57356b75bf2ea54/81615877128.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e523fc6de2---57290306002.pdf
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/pf0c49ukvoje368a6bair4a16v/debisesozobizoribewubam.pdf
    • http://bigyikesmedia.com/home/xtremweb/public_html/consultinstitute/web/upload/files/sotazuvokedug.pdf
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/160dc311ccb611---texelowoboji.pdf
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/59d846cc2edce20dc6bb86f24defecac/99982961986.pdf
    • http://nessium.fr/userfiles/file/padewaraziredavuzixefaxub.pdf
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160a28a1ac8ea0---11230349370.pdf
    • http://casier-a-bouteilles.fr/file/kiwuletorusokutagivugunal.pdf
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/a67ki8n30gfa18sikuikb35ccl/15046351262.pdf
    • http://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/dde6f2a84b25ed563f6dafa05945b402/94629840491.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=resolution+14+of+2002+grievance+form
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010671.bin
7b228ffb595d45a6c4fa94d4951ee486e4c822c24273fd68e9994f4edbdf78d5
pdf-font-stream PDF embedded font (sfnt) at offset 0x10671 16376 bytes
font_01_sfnt_off000130e4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x130E4 16792 bytes
font_02_sfnt_off000148fb.bin
d49709c93857713bac65fd43fe96f78737b7e2a0bc6526fa676af358ff7a8f2f
pdf-font-stream PDF embedded font (sfnt) at offset 0x148FB 11264 bytes